Field of the Invention
The disclosure relates to a method of manufacturing a sealed battery.
Description of the Background Art
A sealed battery includes an electrode body and a housing case for housing the electrode body, and the housing case is formed by welding a lid to a case body having an opening. In recent years, from the perspective of shortening the manufacturing time, continuous welding with a continuous wave-type laser welder has been under study.
When continuous welding is performed with a laser beam, fumes are generated from a welded part, and the laser beam may interfere with particles of the fumes or may be diffused by the particles. When the laser beam is diffused, the laser beam does not reach the welded portion. As a result, a sufficient melting depth cannot be obtained, which may lead to poor welding.
Japanese Patent Laying-Open No. 2009-245758 suggests several methods for suppressing the aforementioned influence of the fumes.
As one of the manufacturing methods described in Japanese Patent Laying-Open No. 2009-245758, a method of repeating a low laser scanning speed and a high laser scanning speed is described. As another manufacturing method, a method of performing laser scanning over the length of 0.8 mm at a prescribed scanning speed, and thereafter, returning by 0.2 mm from a stop position and performing laser scanning again over the length of 0.8 mm is described.
In addition, Japanese Patent Laying-Open No. 2011-212711 describes a method of emitting a laser beam in a pulsed manner in a welding start region and a welding end region, and emitting a laser beam in a continuous manner in a region between the start region and the end region.